Dr.
Sebahattin Tüzemen is visiting the Physics Department at Wake Forest University
for 6 months (November '00 - May '01) as a Fulbright Scholar. Dr. Tüzemen is
Dean of the Faculty of Arts and Sciences and Professor of Physics at Atatürk
University in Erzurum, Turkey. He will be working with Prof. Richard Williams,
Dr. Burak Ucer, and students at Wake Forest on effects of point defects and
their spatial uniformity in III-V materials.
Dr. Tüzemen describes the goal of his project in the following way: Active optical and electronic devices characteristically work at non-equilibrium conditions. Therefore, recombination types and mechanisms play important roles in the quantum efficiency and other characteristics of the devices. The recombination processes proceed via defect centers in the material. In non-equilibrium conditions, due to the change of quasi Fermi levels for both electrons and holes, the parameters of the materials are controlled by minority carriers rather than majority carriers. Therefore it is important to recognize non-radiative recombination centers and to find out the mechanisms. It is also important that recombination centers are uniformly distributed across wafers where the devices are constructed. Therefore, mapping of these defects comes out as an important issue in device manufacturing. The project that Dr. Tüzemen is undertaking at Wake Forest involves i) Recognition of non-radiative recombination centers and the mechanisms by which non-radiative recombination occurs in III-V materials. ii) Mapping the non-radiative recombination centers. This will also involve developing novel mapping techniques.
Dr. Tuzemen's project meshes well with work on photoluminescence, confocal luminescence imaging, ultrafast spectroscopy, and laser photoelectron spectroscopy and imaging conducted in the laboratory of Richard Williams and Burak Ucer by graduate students Gang Xiong, Difei Liang, John Wilkinson, Yong Qiu, and Yonas Abraham. The work may also involve deep level transient spectroscopy and thermally stimulated current measurements in the laboratory of Prof. Rick Matthews.
Dr. Tüzemen's wife Aycha and son Mert (age 3) are in Winston-Salem with him.